The present invention is directed to a method and a device to continuously form packets of box blanks such as folded boxes which are delivered from a delivery station of a folder-gluer device or apparatus which packets are further processed in an additional processing device or apparatus.
Several devices, which create batches of folded box blanks as they are received from a flow of box blanks from an apparatus such as a folder-gluer and make packets of the batches, are already well known. To facilitate the storing of the packet and the piling-up of the various packets, the batches are arranged in a head-to-tail arrangement. An example of a device forming the packets is disclosed in Swiss Pat. No. 572,433 of Dec. 31, 1975 which corresponds to U.S. Pat. No. 3,970,202. In this device, a packet is made up of two batches of folded box blanks which batches are arranged head-to-tail. A first batch is formed in a piling-up station by means of a lower conveyor. As soon as the desired number of boxes for the first batch is received in the piling-up station, a mechanism is actuated to deviate the arriving flow of boxes to a second or upper conveyor which transports the boxes onto a rotating grate of a second piling-up unit. As soon as this second batch of folded boxes is completed, the supply or flow of folded boxes is stopped and the rotating grate is shifted in order to lay the second batch down in a head-to-tail relationship on top of the first batch which is still located in the first piling-up unit. The packet formed in this way is then removed for instance by means of a conveyor arrangement that extends underneath the first piling-up unit.
Another device also piles up two batches of folded box blanks. In this device, the first batch is made up in a piling-up station by means of the conveyor with a rotative plate pivoting in a traveling direction of the boxes. The first batch is made up of the folded box blanks piling up on the rotating plate, and as soon as the desired number of boxes is reached, it is pivoted by 180.degree.. Then the rotating plate bearing the first batch is lowered and a piling-up of a second batch on top of the first one can start. This device is disclosed in German Pat. No. 2,827,540 which corresponds to U.S. Pat. No. 4,264,255.
An advantage of both of the above mentioned devices is that it allows the elimination of manual turning of the batches of the folded box blanks. However, the first mentioned device has a disadvantage of requiring two separate units to form the first and second batches of folded box blanks, rotating means with a heavy mechanism which are required to overcome the effect of the weight of the batches when the batches of folded boxes are pivoted and finally the device requires two separate conveyors to form the batches of folded boxes.
The second mentioned device has the drawback that it turns the batches of folded boxes horizontally. In the tying of the resultant packet of the two batches, the folded boxes are not facing their opposite one in the packet. Another drawback of both devices is that the folded boxes are not always solidly gripped when the batches are stored and might be mixed up during the various operations. Moreover, both devices require a new start for each cycle and this continual starting and stopping excludes a continuous working mode of the device.